How to import JSON file on Jest tests?

Question

I'm testing my application using Jest, but it's getting an error like:

SyntaxError: Unexpected token }

The line witch's occurring error is:

import { something } from "../my-json.json";

How can I import the JSON file on Jest tests?

Answer 1

As decribed here: is there a require for json in node.js you can use:

import someObject from ('./somefile.json')

This should also work:

const testObject = require('../config/object');

However, while i was using jest for testing i got it working by saving the json with .js extension and inside it using module.exports. Then i destructured the object in my main file.

• JSON file (object.js):

  module.exports = {
    "testObject":
    {
        "name": testName
        "surname": testSurname
    }
  }
  

• Main File

  const { testObject } = require('./config/object');
  

Answer 2

Works with Typescript / ts-jest 26.5 :

import * as myJson from './mock/MyJson.json';

...

const result = doAnyting(myJson);

Answer 3

When using Typescript and Vue CLI, all I needed to do was to add resolveJsonModule to tsconfig.ts:

// tsconfig.ts

{
  "compilerOptions": {
    "resolveJsonModule": true,
  }
}

---

This in fact solves the loading of JSON files by Typescript in general.

Note: I am using Vue CLI so it is possible that some JSON related config is already preconfigured there.

Answer 4

You need to import json from 'filename.json'. Make sure that if you're using path alias you need to configure them on your jest.config.js file inside the ModuleNameMapper config.

Answer 5

const myJSON = require('./json_file_name.json')

Note that myJSON is already an object, no need to use JSON.parse

Answer 6

const someObject = require('./somefile.json')

Answer 7

Set "esModuleInterop": true, in tsconfig.spec.json compilerOptions.

Answer 8

You need to remove ',' before all the '}'. I found this solution by test and error.